Influence of Metallization Annealing on Channel Mobility in 4H-SiC MOSFET on Carbon Face

Abstract

4H-SiC MOSFET on carbon face exhibits the high channel mobility when the gate oxide is formed by pyrogenic wet oxidation. However, this improvement is not proof against the metallization annealing which is indispensable in the fabrication of the SiC power MOSFETs. We develop the alternative metallization process suitable for the high channel mobility on the carbon face. The metallization annealing in hydrogen ambient has much effect to suppress the degradation of the channel mobility. The lateral MOSFET with the ohmic contact formed by hydrogen annealing exhibits the high channel mobility which is comparable to the channel mobility of the lateral MOSFET formed without metallization annealing.